Pipe connections

ABSTRACT

A pipe connection has a coupling with one or more socket ends, the or each of which is defined by a circumferential wall surround in which a plurality of four spaced apertures are provided. An annular seal is provided at the inner end of the or each socket end. A collet is provided for location in the or each socket end, the or each collet has a corresponding plurality of four spaced resiliently mounted legs. The legs are co-parallel with the axis of the collet and has similar barb portions each to enter and be held in a corresponding aperture of the respective socket end whereby to hold the collet and therefore the seal in portion in the or each socket end.

BACKGROUND OF THE INVENTION

1. Field of Invention

This invention relates to pipe connections through which lengths ofpiping can be coupled into a pipe system for use particularly, but notexclusively, in a mobile structure, for example a caravan, or a boat.The connections are couplings which may be in any form, for examplestraights, elbows or T-junctions, with each coupling having one or moresocket ends into each one of which socket ends a leading end of a lengthof piping is fitted.

2. Summary of the Invention

Accordingly, the present invention is a pipe connection having acoupling with one or more socket ends defined by a circumferential wallsurround in which a plurality of spaced apertures are provided, anannular seal provided at the inner end of each socket end and a colletfor location in each socket end, each collet having a correspondingplurality of spaced resiliently mounted legs to the plurality ofapertures, the legs being co-parallel with the axis of the collet andhaving similar barb portions each to enter and be held in acorresponding aperture of the respective socket end whereby to hold thecollet, and therefore the seal in position in the socket end.

Each collet preferably has two similar rings, an inner ring and an outerring, spaced apart axially and held together by a series of postsforming a cage which rigidly supports the piping. Between each twoadjacent posts and the rings, a window is beneficially defined in whichone of the legs is positioned, the leg being rooted to the outer ringwith the leg extending towards the inner ring. A collet is desirablyintended for positioning in the respective socket end with the distalends of the legs directed innermost and with the inner ring innermost.The outer ring beneficially is an angular flange which overlies theouter end of a socket end into which a collet is fitted. The portion ofthe inner ring in each window has preferably a castellation extendinginto the window and whose purpose is to restrict inward movement of arespective leg beyond a predetermined limit.

The barb portion for each leg preferably has an outward downwardlysloping face, and an inward radial face, the sloping face commencinginward of the outer ring inclining to stop short of the outer edge ofthe radial face to form a ledge, the barb portion, when engaged in anaperture, preventing removal of the collet from the respective socketend. Each leg is similar and its inner face may be radially curved alongits length.

An inner part of the socket end preferably is of reduced diameter with afirst shoulder provided against which the collet lies. The seal may bean O-ring provided to seat between the shoulder and the inner ring of arespective collet.

Preferably, the wall surround of the socket end towards the end face iscut-away between the outer and inner edges of the wall surround toprovide an inwardly sloped guideway leading inwards to assist in ariding movement of the outer end of the radial face of the barb portionsof the legs into the socket end, the riding movement flexing the legsinwardly with the legs returning to their normal position when the barbportions enter respective apertures. The sloped guideways are desirablyradially offset from the apertures requiring the collet to be insertedthen rotated for the barb portions to be aligned with and enter thecorresponding apertures. The portions of the inside of the wall surroundof the socket end between the end face and each window is beneficiallyprovided with a swelling.

Preferably also, each leg has on its inner face opposite to the barbportion, a gripping edge. The gripping edges of the legs together form abroken internal circumferential zone for gripping the outside face of aleading end of a length of piping. The inner edge of the radial face atits junction with the inner face of each finger forms a heel, the heelsof the fingers forming a second broken internal circumferential zone.Each leg is desirably provided with a knee at the start of the slopingface of the barb portion and extending along the barb portion apredetermined distance.

Each coupling, collet and piping are preferably of rigid material,either of synthetic plastics material or of a metal or of a metal alloy.The piping of semi-rigid plastics material allows the gripping edges tobite into its surface. However, if the piping is of a rigid plasticsmaterial, a metal or a metal alloy, two spaced annular recesses areprovided into which the gripping edges and heels locate.

Preferably further, a tubular cover is provided to be located aroundeach socket end to close off the apertures. The end of the tubular coverat the outer ring is beneficially extended and scalloped to mask thecollet from unintentional inward movement.

BRIEF DESCRIPTION OF THE DRAWINGS

An embodiment of the present invention will now be described, by way ofexample, with reference to the accompanying drawings, in which:

FIGS. 1A and 1B are respectively a cross-sectional view of a pipeconnection according to the present invention showing a socket end, anO-ring seal and a collet, and a cross-sectional view of a collet.

FIGS. 2A and 2B are respectively a cross-sectional view of a pipeassembly including a connection and a leading end of a length of pipe,and a cross-sectional view of a collet with fingers displayed; and

FIGS. 3A and 3B are respectively a cross-sectional view of the pipeassembly when the piping is being pulled outwardly and a cross-sectionalview of a collet with fingers inwardly displaced.

Referring to the drawings, a pipe connection has a coupling 10 with oneor more socket ends 12, each of which is defined by a circumferentialwall surround 14 in which a plurality of four equi-spaced apertures 16are provided, an annular seal 18 provided at the inner end of the socketend 12 and a collet 20 for location in the socket end 12. The collet 20has a corresponding plurality of four equi-spaced resiliently mountedlegs 22, i.e., the same number as in the plurality of apertures 16. Thelegs 22 are co-parallel with the axis of the collet 20 and has similarbarb portions 24 each to enter and be held in a corresponding aperture16 of the respective socket end 12 whereby to hold the collet 20, andtherefore the seal 18 and any piping 26 therein, in position in thesocket end 12.

Each collet 20 has two similar rings, an inner ring 28 and an outer ring30 spaced apart axially and held together by a series of posts 32forming a cage which serves to fully support the piping 26 thuspreventing leakages resulting from side loads on piping 26 or ovality inthe piping 26. The inner ring 28 also serves as a washer. Between eachtwo adjacent posts 32 and the rings 28, 30, a window 34 is defined inwhich one of the legs 22 is positioned with the leg 22 being rooted tothe outer ring 30 and extending towards the inner ring 28. A collet 20is intended for positioning in the respective socket end 12 with thedistal ends of the legs 22 directed innermost and with the inner ring 28innermost.

The outer ring 30 is an annular flange which overlies the outer end of asocket end 12 into which a collet 20 is fitted. The portion of the innerring 28 in each window 34 has a castellation 35 mid-way of the portionextending into the window 34 and whose purpose is to restrict inwardmovement of a respective leg 22 beyond a predetermined limit.

The barb portion 24 for each leg 22 has an outward downwardly slopingface 36, and an inward radial face 38. The sloping face 36 commencesinward of the outer ring 30 and inclining to stop short of the outeredge of the radial face 38 to form a ledge 40. The barb portion 24, whenengaged in an aperture 16, prevents removal of the collet 20 from therespective socket end 12. Each leg 22 is similar and its inner face isradially curved about its length. If the piping is pulled outwardly, thesloping face 36 of each barb portion, acting on the aperture surroundcauses the gripping edges to be described hereinafter to bite furtherinto the piping to prevent removal.

An inner part of the socket end 12 is of reduced diameter with a firstshoulder 42 provided against which the inner ring 28 of the collet 20lies. The reduced diameter part of the socket end 12 is further reducedcreating a second shoulder 43 against which the leading end of a lengthof piping 26 abuts. The seal 18 is an O-ring provided to seat betweenthe first shoulder 42 and the inner ring 28 of a respective collet 20.

The wall surround 14 of the socket end 12 towards the end face iscut-away between the outer and inner edges of the wall surround 14 toprovide an inwardly sloped guideway 44 leading inwards to assist in ariding movement of the outer end of the radial face 38 of the barbportions 24 of the legs 22 into the socket end 12, the riding movementflexing the legs 22 inwardly with the legs 22 returning to their normalposition when the barb portions 24 enter respective apertures 16. Thesloped guideways are radially offset by forty-five angular degrees fromthe aperture requiring the collet 20 to be inserted then rotated throughforty-five angular degrees for the barb portions 24 to be aligned withand enter the corresponding apertures 16. The portions of the inside ofthe wall surround of the socket end 12 between the end face and eachaperture 16 is provided with a swelling 37.

Each leg 22 has on its inner face opposite to the barb portion 24, agripping edge 46. The gripping edges 46 of the legs 22 together form abroken internal circumferential zone for gripping the outside face of aleading end of a length of piping 26. The inner length of the radialface 38 at its junction with the inner face of each leg 22 forms a heel47, the heels 47 of the legs 22 forming a second broken internalcircumferential zone. Each leg 22 is provided with a knee 23 at thestart of the sloping face 36 of the barb portion 24 and extending alongthe barb portion 24 a predetermined distance.

The piping 26 can be removed from the respective collet 20 by inwardlypressing the outer ring 30 of the collet 20 and pulling the piping 26outwards.

Each coupling 10, collet 20 and piping 26 preferably are of rigid orsame rigid material, either of synthetic plastics material or of a metalor of a metal alloy. The piping 26 of semi-rigid plastics materialallows the gripping edges 46 and heels 47 to bite into its surface.However, if the piping is of a rigid plastics material, metal or a metalalloy, two suitably positioned annular recesses 48, 49 are provided intowhich the gripping edges 46 and heels 47 locate. Also, if two couplings,are to be connected together, a spigot end is provided on one coupling10 having two annular recesses.

A tubular cover 52 is provided to be located around each socket end toclose off the apertures 16. The end of the tubular cover 52 at the outerring 30 is extended beyond the outer ring 30 and is scalloped. The cover52 is to mask the outer ring 30 of the collet 20 and prevent it fromunintentional inward movement. The tubular cover 52 has an internalcircumferential rib 53 to mate with a corresponding external groove 55on each socket end 12.

Pipe connections of the type described above allow for rapid assembly ofa pipe system with the ends of lengths of piping 26 simply beingpush-fitted into socket ends of couplings. The connections give secureliquid-sealed joints.

In use, a pipe system is fabricated as required using pipe connectionsas hereinbefore described with the ends of the lengths of piping 26being pushed into the collets 20 until the ends abut the respectivesecond shoulder 43, the O-ring seat 18 being tightly fitted around thepiping 26 to prevent leakage of fluid passing through the piping 26 andthe connections, and the gripping edges of the collet 20 holding thepiping 26 from removal, gripping edges 46 biting into the respectivepiping to prevent removal.

In a normal flow pipe system, there is a normal temperature rating and anormal pressure rating. However, in certain circumstances either or boththese ratings can increase. It has been found in test that a pipeconnection with piping therein as above described will not separateunder extreme pressure, but rather the collet will move to an outwardposition in its location in its respective socket end which enables theseal to move up and corresponding parts will enter the apertures andallow release of a necessary amount of fluid to bring down the pressureand will then return to its normal position without suffering damage.Thus the individual connections between piping and respective pipeconnections each serves as a pressure relief valve. This is a verybeneficial advantage of this invention.

The design of the collet cage significantly reduces the risk of leakagepassed the O-ring seal.

In a modification, more or less than four apertures 16 and acorresponding number of legs 22 with barb portions 24 can be provided.

Variations and other modifications can be made without departing fromthe scope of the invention described above and as claimed hereinafter.

The foregoing relates to preferred exemplary embodiments of theinvention, it being understood that other variants and embodimentsthereof are possible within the spirit and scope of the invention, thelatter being defined by the appended claims.

We claim:
 1. A pipe connection having a coupling with a socket enddefined by a circumferential wall surround having outer and inner edgesand in which a plurality of peripherally-spaced radial apertures areprovided, an annular seal provided at the axial inner end of the socketend and a single piece collet provided for location in the socket end,the collet having a corresponding plurality of spaced resilientlymounted, radial legs to the plurality of apertures, the collet having alongitudinal axis with the legs being parallel with the collet axis andhaving similar outwardly-projecting barb portions each to enter and beheld in a corresponding aperture of the socket end whereby to hold thecollet, and therefore the seal in position in the socket end, the collethaving two complete rings of similar diameter, a first or inner ring forlocation at the axial inner end of the socket end, and a second or outerring for location at the axial outer end of the socket end, the ringsbeing spaced apart axially and held together by a series of postsforming a cage which, in use, rigidly supports a leading end of a lengthof pipe fitted thereinto, each two adjacent posts and the rings of thecage cooperating to define a window in which one of the legs ispositioned, a portion of the inner ring of each window having acastellation extending into the window to restrict inward movement of arespective leg beyond a predetermined limit.
 2. A pipe connectionaccording to claim 1, wherein the leg in each window is rooted to theouter ring with the leg extending towards the inner ring.
 3. A pipeconnection according to claim 1, wherein the collet is adapted to bepositioned in the socket end with the distal ends of the legs directedinnermost and with the inner ring innermost.
 4. A pipe connectionaccording to claim 1, wherein the outer ring is an annular flange whichoverlies the outer end of a socket end into which the collet is fitted.5. A pipe connection according to claim 1, wherein the barb portion foreach leg has an outward downwardly sloping face, and a rearward radialface, the sloping face commencing inward of the outer ring and stoppingshort of the outer edge of the radial face to form a ledge.
 6. A pipeconnection according to claim 5, wherein portions of the wall surroundof the socket end is cut-away between the outer and inner edges of thewall surround to provide a plurality of inwardly sloped guidewaysleading inwards to assist in a riding movement of the outer end of theradial face of the barb portions of the legs into the socket outer end,the riding movement flexing the legs inwardly with the legs returning totheir normal position when the barb portions enter respective apertures.7. A pipe connection according to claim 6, wherein the sloped guidewaysare radially offset from the apertures requiring the collet to beinserted then rotated for the barb portions to be aligned with and enterthe corresponding apertures.
 8. A pipe connection according to claim 5,wherein each leg is provided with a knee at the start of the slopingface of the barb portion and extending along the barb portion apredetermined distance.
 9. A pipe connection according to claim 1,wherein each leg is similar and its inner face is radially curved alongits length.
 10. A pipe connection according to claim 1, wherein an innerpart of the socket end is of reduced diameter defining a first shoulderproviding a stop for the inner ring of the collet.
 11. A pipe connectionaccording to claim 10, wherein the seal is an O-ring provided to seatbetween the first shoulder of the socket end and the inner ring of therespective collet.
 12. A pipe connection according to claim 1, whereinportions of the inside wall of the wall surround of the socket endbetween the end face and each aperture is provided with a swelling. 13.A pipe connection according to claim 1, wherein each leg has on itsinner face opposite to the barb portion, a gripping edge.
 14. A pipeconnection according to claim 13, wherein the gripping edges of the legstogether form a broken internal circumferential zone for gripping theoutside face of a leading end of a length of pipe.
 15. A pipe connectionaccording to claim 14, wherein the inner edge of the radial face of eachbarb portion at its junction with the inner face of each leg forms aheel, the heels of the legs forming a second broken internalcircumferential gripping zone.
 16. A pipe connection according to claim1, wherein a tubular cover is provided to be located around the or eachsocket end to close off the apertures.
 17. A pipe connection accordingto claim 16, wherein the tubular cover has an internal circumferentialrib to mate with a corresponding external groove in each socket end. 18.A pipe connection according to claim 17, also wherein the end of thetubular cover at the outer ring is extended and scalloped to mask thecollet from unintentional inward movement.
 19. A pipe assemblycomprising one or more pipe connections according to claim 1, and alength of piping pushed into the collet in the or each socket end.
 20. Apipe assembly according to claim 19, wherein the leading end of thelength of piping when of rigid material is provided with two spacedannular recesses into which the gripping edges and heels of a respectivepipe connection locate.